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This paper presents the results of studies on the effects of four types of aerosols containing an aqueous dispersed suspension of graphene oxide (GO) and an aqueous dispersed suspension of graphene oxide with the addition of curcumin (GO + C), silver nanoparticles (GO + Ag), and hypochlorous acid (GO + HClO) on selected structural and biological properties. Structural studies were carried out using electron microscopy, including a scanning electron microscope (SEM), scanning transmission electron microscopy (STEM), laser emission spectroscopy (LIBS), and absorption spectra in the infrared range attuned total reflectance (FTIR-ATR). The growth inhibition zone and viability of Staphylococcus aureus and Pseudomonas aeruginosa bacteria were studied. Studies have shown that the addition of silver nanoparticles and hypochlorous acid to the nanostructures of graphene oxide suspension improves bactericidal properties. In addition, it was observed that the application of a dispersed graphene oxide suspension in the form of an aerosol enriched with hypochlorous acid and silver nanoparticles results in the formation of a fairly uniform layer of graphene flakes, characterized by the presence of admixtures used.

This paper presents the results of research on the impact of graphene paper on selected bacterial strains. Graphene oxide, from which graphene paper is made, has mainly bacteriostatic properties. Therefore, the main goal of this research was to determine the possibility of using graphene paper as a carrier of a medicinal substance. Studies of the degree of bacterial inhibition were performed on Staphylococcus aureus and Pseudomonas aeruginosa strains. Graphene paper was analyzed not only in the state of delivery but also after the incorporation of the antibiotics ciprofloxacin, cefazolin, and methicillin into its structures. In addition, Fourier-Transform Infrared Spectroscopy, contact angle, and microscopic analysis of bacteria on the surface of the examined graphene paper samples were also performed. Studies have shown that graphene paper with built-in ciprofloxacin had a bactericidal effect on the strains of Staphylococcus aureus and Pseudomonas aeruginosa . In contrast, methicillin, as well as cefazolin, deposited on graphene paper acted mainly locally. Studies have shown that graphene paper can be used as a carrier of selected medicinal substances.

The study aimed to test the durability of coatings under natural conditions. The present study focused on the changes in wettability and additional properties of the coatings under natural conditions. The specimens were subjected to outdoor exposure and additionally immersed in the pond. Impregnating porous anodized aluminum is a popular production method for hydrophobic and superhydrophobic surfaces. However, prolonged exposure of such coatings to natural conditions causes leaching of the impregnate and, thus, the loss of hydrophobic properties. After the loss of hydrophobic properties, all kinds of impurities and fouling adhere better to the porous structure. Additionally, deterioration of anti-icing and anti-corrosion properties was observed. Finally, the self-cleaning, anti-fouling, anti-icing and anti-corrosion properties were comparable or even worse to those of the hydrophilic coating. In the case of superhydrophobic specimens, during outdoor exposure there was no loss of superhydrophobicity, self-cleaning and anti-corrosion properties. Still, despite this, the icing delay time dropped. During outdoor exposure, the structure, which initially had anti-icing properties, may degrade. Nevertheless, the hierarchical structure responsible for the superhydrophobic effect can still be preserved. The superhydrophobic coating initially had the best anti-fouling properties. However, the coating was also gradually losing its superhydrophobic properties during water immersion.

The aim of this study was to obtain a superhydrophobic coating by modifying anodized aluminum using polydimethylsiloxane (PDMS). In order to obtain a superhydrophobic coating on an aluminum substrate, a multistage treatment was implemented. Specimens of aluminum were treated by abrasive blasting, anodization in sulfuric acid, impregnation by PDMS, rinsing in toluene to remove excess of PDMS, and curing. A rough surface with an additional low free energy layer on it resulted in a superhydrophobic effect. The coating obtained has an average contact angle of 159°. The specimens were tested in terms of durability in natural conditions. Additionally, anti-icing and anti-fouling properties were evaluated. The coating was compared with anodized aluminum obtained by a basic process.